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PRICE 25 CENTS 




DIE CASTING 

DIES-MACHINES-METHODS 

BY CHESTER L. LUCAS 




MACHINERY'S REFERENCE BOOK NO. 109 
PUBLISHED BY MACHINERY. NEW YORK 



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MACHINERY'S REFERENCE BOOKS 

This treatise is one unit in a comprehensive Series of Reference books originated 
by Machinery, and including an indefinite number of compact units, each covering 
one subject thoroughly. The whole series 'comprises a complete working library 
of mechanical literature. The price of each book is 25 cents (one shilling) de- 
livered anywhere in the world. 

LIST OF REFERENCE BOOKS 



No. 1. Worm Gearing. — Calculating Dimensions; 
Hol)s; Looation of ritch Circle; Self-Loeljing 
Worm Gearing, etc. 

No. 2, Drafting-Room Practice.— Systems : Trac. 
ing. Lettering and Mounting. 

No. 3. Drill Jigs. — Principles of Drill Jigs; Jig 
Plates; Examples of Jigs. 

No. 4. Milling Fixtures. — Principles of Fix- 
tures; Examples of Design. 

No. 5. First Principles of Theoretical Mechanics. 

No. 6. Punch and Die' Work. — Principles of 
I'uncli and Die Worlj; Making and Using Dies; 
Die and Punch Design. 

No. 7. Lathe and Planer Tools. — Cutting Tools; 
rior'ng Tools; Shape of Standard Shop Tools; 
Forming Tools. 

No. 8. Working Drawings and Drafting.Room 
Kinks. 

No. 9. Designing and Cutting Cams. — Drafting 
of Cams; Cam Curves; Cam Design and Cam 
Cutting. 

No. 10. Ilzamples of Machine Shop Practice. — 
Cutting Bevel (Jears; Making a Worm.Gear; 
Spindle Construction. 

No. H. Bearings. — Design of Bearings; Causes 
of Hot Bearings; Alloys for Bearings; Friction 
and Lubrication. 

No. 12. Out of print. 

No. 13. Blanking Dies. — Making Blanking Dies; 
Blanking and Piercing Dies; Split Dies; Novel 
Ideas in Die Making. 

No. 14. Details of Machine Tool Design. — Cone 
Pulleys and ftelts; .Strength of Countershafts; 
Tumbler Gear Design; Faults of Iron Castings. 

No. 15. Spur Gearing. — Dimensions; Design; 
Strength; Durability. - 

No, 16. Machine Tool Drives. — Speeds and 
Feeds; Single Pulley Drives; Drives for High 
Speed Cutting Tools. 

No. IT. Strength of Cylinders. — Formulas, 
Charts, 'and Diagrams. 

No. 18. Shop Arithmetic for the Machinist. — 
Tapers: Change (Jears; Cutting Speeds: Feeds; 
InUexinj; Gearing for Cutting Spirals; Angles. 

No. 19. Use of Formulas in Mechanics. — With 
numerous apiilications. 

No. 20. Spiral Gearing. — Rules, Formulas, and 
Diagrams, etc. 

No. 21. Measuring Tools. — History of Standard 
Measurements; Calipers; Compasses; Micrometer 
Tools; Protractors. 

No. 22. Calculatior. of Elements of Machine De- 
sign. — Factor of Safety; Strength of Bolts; Rivet- 
ed Joints; Keys and Kejways; Toggle-joints. 



No. 23. Theory of Crane Design. — Jib Cranes; 
Shafts, Gears, and Bearings; Force to Move Crane 
Trolleys; Pillar Cranes. 

No. 24. Examples of Calculating Designs. — 

Charts in Designing: Punch and Riveter Frames; 
Shear Frames; Billet and Bar Passes, etc. 

No. 25. Deep Hole Drilling. — Methods of Drill- 
ing; Construction of Drills. 

No. 26. Modern Punch and Die Construction. — 
Construction and Use of Subpress Dies; Modern 
Blanking Die Construction; Drawing and Forming 
Dies. 

No. 27, Locomotive Design, Part I. — Boilers, 
Cylinders, Pipes and Pistons. 

No. 28. Locomotive Design, Part II. — Stei)hen- 
son and Walschaerts Valve Motions; Theory, Cal- 
culation and Design. 

No. 29. Locomotive Design, Part III. — Smoke- 
box; Exhaust Pipe; Frames; Cross-heads; Guide 
Bars; Connecting-rods; Crank-pins; Axles; Driving- 
wheels. 

No. 30. Locomotive Design, Part IV. — Springs, 
Trucks, Cab and Tender. 

No. 31. Screw Thread Tools and Gages, 

No. 32. Screw Thread Cutting. — Lathe Change 
Gears; Thread Tools; Kinks. 

No. 33. Systems and Practice of the Drafting- 
Room. 

Nc. 34. Care and Repair of Dynamos and 
Motors. 

No. 35. Tables and Formulas for Shop and 
Drafting- Room. — The U.se of Formulas; .Solution 
of Triangles: .Strength of Materials; Gearing; 
Screw Thre.itls; Tap Drills; Drill Sizes; Tapers; 
Keys, etc. 

No. 36. Iron and Steel, — Principles of Manu- 
failure and Treatment, 

No. 37. Bevel Gearing, — Rules and Formulas; 
Examples of Calculation: Tooth Outlines; Strength 
and Durability; Design; Methods of Cutting Teeth. 

No. 38. Out of print. See No. 98. 

No. 39. Fans, Ventilation and Heating. — Fans; 
Heaters; Shop Heating. 

No. 40. Fly-Wheels.— Their Purpose, Calcula- 
tion and Design. 

No. 41. Jigs and Fixtures, Part I. — Principles 
of Design; Drill Jig Bushings; Locating Points; 
Clamping Devices. 

No. 42. Jigs and Fixtures, Part II. — Open and 
Clo.sed Drill Jigs. 

No. 43. Jigs and Fixtures, Part III. — Boring 
and Milling Fixtures. 

"'Vo. 44. Machine Blacksmithing. — Systems, Tools 
and Machines used. 



(See inside back cover for additional titles) 



MACHINERY'S REFERENCE SERIES 

EACH NUMBER IS ONE UNIT IN A COMPLETE UBRARY OF 

MACHINE DESIGN AND SHOP PRACTICE REVISED AND 

REPUBLISHED FROM MACHINERY 



NUMBER 109 

DIE CASTING 

DIES— MACHINES— METHODS 

By Chester L. Lucas 

CONTENTS 

Die Casting _-______3 

Making Dies for Die-Casting Machines - - - 15 
Van Wagner Mfg. Co.'s Die-Casting Practice - - 27 



Ccpyright, 1913, The Industrial Press, Publishers of Machinery, 
49-55 Lafayette Street, New York City 



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CHAPTER I 



DIE CASTING 

Die-casting, a comparatively recent method for producing finished 
castings, is rapidly proving itself an important factor in the economical 
manufacture of interchangeable parts for adding machines, tj^pewriters, 
telephones, automobiles and numerous other products where it is essen- 
tial that the parts be nicely finished and accurate in dimensions. 
The term "die-casting" is self-explanatoiry, meaning "to cast by means 
of dies"; described briefly, the process consists of forcing molten metal 
into steel dies, allowing it to cool in them, and then opening the dies 
and removing the finished casting. It is the purpose of this treatise 
to give a general outline of the die-casting process, showing its possi- 
bilities and limitations, and also to give a description of the die-casting 
machinery and its operation, of the fundamental principles involved, 
and of the methods used in the die-making. Illustrative examples of 
the best types of dies, based on results obtained from actual experience, 
"will also be given. 

Origin of Die Casting 

The origin of the die-casting process is somewhat difficult to ascer- 
tain. We may look into the history of type founding and find that 
away back in 1S38, the first casting machine for type, invented by Bruce, 
was a machine that involved the principles of die-casting as it is prac- 
ticed to-day. More recently, in 1885, Otto Mergenthaler brought out the 
linotype machine. This machine is a good example of a die-casting 
machine. However, as we interpret the word to-day, die-casting is a 
broader term than type-casting or linotyping, although its development 
without doubt is due to the success of the linotype machine. It is 
doubtful if die-casting, properly speaking, was originated until about 
fifteen years ago, and it is certain that it is only during the past few 
years that the activities in this line have been very noticeable. 

One of the first experiments in the direction of die-casting was under- 
taken to get out some rubber mold parts cheaply enough to leave a 
profit on a job that was beginning to look dubious from the financial 
side. The molds were for making rubber plates about three inches 
square and one-eighth inch thick, the top side of which was decorated 
with fine raised scroll work; it was this latter feature that gave the 
trouble. After wasting much time and money trying to stamp the 
mold parts, a metal-tight box was made as shown in Figs. 1 and 2 
with a block screwed in it, the purpose of which was to shape the mold 
impression and impart to it the scroll design. As shown, the ends of 
the box were removable, being screwed on. This box was placed under 
a screw press and a straight plunger that just filled the top of the box 
was fitted to the head of the press. After the two were lined up, 
molten type metal was poured into the box, and as soon as the metal 
had cooled to the "mushy" state, the ram of the press was forced down 



4 No. 109— DIE CASTING 

as shown in Fig. 2. Next, the ends of the box were removed, the screw 
holding the block taken out, and the die-casting pushed from the box. 
The object in having the inclined side to the box was to produce a piece 
shaped with the proper inclination for its position in the final mold 
used for casting the rubber plates. The illustrations give an idea of the 





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Fig. 1. An Early Experiment in 
Die Casting — Before Applyingr 
Pressure 



Fig-. 2. An Early Experiment in 
Die Casting — After Applying 
Pressure 



compression that took place. The die-casting was found to be sharp 
at the corners and free from flaws, and the scroll work came up in fine 
shape. Naturally the rest of the mold parts were made in the same 
way and the job turned from failure into success. 

From such simple experiments as these, the die-casting industry 
has developed to its present stage. In view of the advances that have 
been made in die-casting, it is singular that there are to-day only 



DIE CASTING 5 

about a dozen concerns in the business in this country, but as the sub- 
ject becomes better understood, and the possibilities of the process are 
realized, the demand for this class of castings will result in many 
other firms going into the work, and it is not improbable that a large 
number of factories will install die-casting plants of their own to aid 
them in producing better work in a more economical way. 

Advantag-es, Possibilities and Limitations of Die Casting 

The greatest advantage of die-casting is the fact that the castings 
produced are completely and accurately finished when taken from the 
dies. When we say completely, we mean that absolutly no machining 
is required after the piece has been cast, as it is ready to slip into its 
place in the machine or device of which it is to be a part. When we 
say accurately, we mean that each piece will come from the die an 
exact counterpart of the last one; and if the dies are carefully made, 
the castings will be accurate within 0.001 inch on all dimensions, 
whether they are outside measurements, diameters of holes or radii. 
All holes are cast and come out smoother than they could be reamed; 
lugs and gear teeth are cast in place; threads, external and internal, 
and of any desired pitch can be cast. Oil grooves can be cast in bear- 
ings, and, in a word, any piece that can be machined can be die-cast. 

The saving in machining works both ways; not only is all machine 
work eliminated by the one operation of casting, but the machine tools 
and the workmen necessary for their operation and up-keep are dis- 
pensed with, the expense of building jigs and fixtures is stopped; and 
no cutters, reamers, taps or drills are required for this branch of the 
production. In addition, the labor required for operating the casting 
machines may be classed as unskilled. No matter how intricate and 
exacting the machine work on a piece has been, and how skillful a 
workman was required to produce the work when machine-made, the 
same result may be brought about by die-casting, and usually the work 
is excelled, and, excluding the die-making, unskilled men can make the 
parts. 

From a metallurgical standpoint a die-casting is superior to a sand- 
casting on account of its density, strength and freedom from blow-holes. 
Also, when the hot metal comes in contact with the cool dies, it forms 
a "skin" similar to the scale on an iron sand-casting. As the die-casting 
requires no machining after leaving the dies, this skin increases the 
wearing qualities of the casting. 

The possibilities of die-casting are numerous. By this method of 
manufacturing it is possible and practical to cast pieces that could not 
possibly be machined. It is an every-day occurrence to make castings 
with inserted parts of another metal, as, for instance, a zinc wheel with 
a steel hub. It is also possible to make babbitt bearings that are harder 
and better than can be made in any other way. Often there are two or 
more parts of a device that have formerly been made separately, ma- 
chined and assembled, that can be die-cast as one piece. In such cases 
the saving in production is very great. Figures and letters may be 
cast sunken or in relief on wheels for counting or printing, and of 



6 No. 109— DIE CASTING 

course ornamentation may be cast on pieces that require exterior finish. 
As to size, there is no definite limit to the work that can be cast. 
One job that is being done at the present time is a disk 16 inches in 
diameter with a round flange 1 inch in diameter, around the rim. 

"There is no great gain without some small loss," is just as true of 
a process like die-casting as it is of anything else. The limitations 
of this work are few, however, and they are here given so as to state 
the situation fairly. Generally speaking, a part should not be consid- 




Figr. 3. Examples of Die-castingrs 

ered for die-casting if there are but few pieces required, because the 
cost of the dies would usually be prohibitive. Often, however, it hap- 
pens that because of the large amount of accurate machine work being 
done on a machine part, it is economical to make a die for the com- 
paratively small number of parts required and die-cast them. A case 
illustrating this phase of the matter recently occurred in actual prac- 
tice. In getting out an order of two hundred vending machines, it 
was decided to try die-casting on a part that was difficult to machine. 
The dies were expensive, costing $200, and as there were only 200 pieces 



DIE CASTING 7 

to be cast, the die cost per piece was one dollar; but even with that 
initial handicap, it was found that on account of the difficult machining 
that had formerly been required, the die-cast parts effected a large 
saving, and of course the results were superior. 

A rough part that would require little or no machining should not be 
die-cast, because pound for pound, the die-casting metals cost more than 
cast iron or steel. The casting machine cannot make parts as rapidly 
or of as hard metals as the punch press or the automatic screw machine. 
For this latter reason a part that necessarily must be made of brass, 
iron or steel, cannot be die-cast, although mixtures approximately equal 
in strength to iron and brass are readily die-cast. To give added 
strength to a die-cast part it is often advisable to add webs and ribs or 
to insert brass or iron pins at points that are weak or subject to hard 
wear. Roughly speaking, it is the part that has required a good deal 
of accurate machine operations that shows the greatest difference in 
cost when die-cast, and sometimes the saving is as great as 80 per 
cent. 

The Metals used in Die Casting- 

The metals that produce the best die-castings are alloys of lead, tin, 
zinc, antimony, aluminum and copper, and the bulk of the die-castings 
made at the present time are mixtures of the first four of these metals. 
From them, compositions may be made that will meet the requirements 
of nearly any part. 

For parts that perform little or no actual work, save to "lend their 
■weight," such as balance weights, novelties and ornaments for show 
windows, etc., a mixture consisting principally of lead, often stiffened 
with a little antimony, is used. There is but little strength to this 
metal, but it is used because of its weight and low cost. For parts that 
are subject to wear, such as phonograph, telephone, gas-meter and 
adding machine parts, an alloy composed of zinc, tin and a small 
amount of copper is used. This alloy may be plated or japanned, and is 
a good metal to use on general work 

Another metal, used chiefly for casting pieces that have delicate 
points in their design but are not subjected to hard wear, consists prin- 
cipally of tin alloyed with lead and zinc to suit the requirements of the 
work. This mixture casts freely, and the finished castings come out 
exceptionally clean. Still another metal, used chiefly for casting pieces, 
that have letters and figures for printing, is similar to the standard 
type metal — 5 parts lead and 1 part antimony; but if there are teeth 
cast on the sides of the printing wheel a harder mixture will be re- 
quired to give longer life to the gears. 

The following mixtures are typical of die-casting or "white brass" 
alloys: copper, 10 parts; zinc, 83 parts; aluminum, 2 parts; tin, 5 parts. 
Another is copper, 6 parts; zinc, 90 parts; aluminum, 3 parts; tin, 1 
part. Another containing antimony is copper, 5 parts; zinc, 85 parts; 
tin, 5 parts; antimony, 5 parts. Shonberg's patented alloy is copper, 3 
parts; zinc, 87 parts; tin, 10 parts. Alloys containing 15 to 40 per 
cent copper and 60 to 85 per cent zinc are brittle, having low strength 



8 



No. 109— DIE CASTING 



and low ductility. An alloy of 8 per cent copper, 92 per cent zinc has 
greater resilience and strength but not the ductility of cast zinc. 

Aluminum may be cast, but it is a difficult metal to run into thin 
walls and fine details; it plays, however, an important part in some 
good mixtures used for die casting. Experiments are now being con- 
ducted for die-casting manganese bronze, and it is said that some Tery 




Pig, 4. General View of tbe Soss Die-casting Machine 

good castings have already been made. Its wearing qualities are so 
valuable that it is particularly desirable for making die-castings. 

The Die-casting' Machine 
The three important requisites for good die-casting are the machine, 
the dies and the metal. The casting machine is fully as essential as 
either of the other requisites, and although there are a number of 
different styles of casting machines in use, each of which has its 
advantages over the others, especially in the eyes of their respective 
designers, the fundamental principles upon which they all operate are 
the same. In each there is the melting pot and the burner, the cylinder 
and the piston foT forcing the metal jnto the dies, and the dies with 



DIE CASTING 9 

the opening and closing device. In some machines pressure is applied 
to the metal by hand, in others power is used, and in still another class 
the metal is forced into the dies with compressed air. The provisions 
for opening and closing the dies vary in the different machines; there 
are various means employed for cutting the sprue, and the styles of 
heaters are numerous. 

One or two of the largest firms in the die-casting industry have 
automatic casting machines for turning out duplicate work in large 
quantities very rapidly. These machines are complicated and are only 
profitable on large quantities of work, and for that reason their use 
is not extensive. In general, their operating principles are the same 
as in the case of the hand machines, but provision is made for auto- 
matically opening and closing the dies, compressing the metal, and 
ejecting the castings. 

The Soss Die-casting Machine 

The Soss die-casting machine, manufactured and sold by the Soss 
Manufacturing Co., Brooklyn, N. Y., was the first die-casting machine 
to be placed on the open market. This machine is shown in Figs. 4 and 
5, and in section in Fig. 6. The Soss Manufacturing Co. originally 
manufactured invisible hinges exclusively. At the advent of the die- 
casting era, they commenced to make these hinges from die-castings, 
and placed orders with a leading die-casting concern amounting to 
thousands of dollars each year. After the die-cast hinges had been on 
the market for a short time, complaints commenced to come in. some 
to the effect that the hinges were breaking and others that the hinges 
were corroding. Either of these faults was serious enough to blast 
the reputation of the hinge, but the first trouble, breakage, was the 
more important. Examination of the broken hinges showed that the 
castings were porous and full of flaws, and as the makers of the cast- 
ings could not produce castings sufficiently strong for the hinges, Mr. 
Soss started to experiment for himself. This experimenting led to the 
production of the Soss die-casting machine. 

Referring to the illustrations Figs. 5 and 6, A is the base and frame 
of the machine, B is the heating chamber located at one end of the 
machine, and within this heating chamber is the tank C. shown in 
Fig. 6. This tank contains the metal from which the die-castings are 
made, and the metal is heated by the burners D. These burners are fed 
by air and gas through piping on the side of and beneath the furnace. 
To facilitate lighting the burners and inspecting their condition at 
any time, there is an opening (not shown) through the firebrick lining 
of the furnace and the outer iron wall, on a level with the top of the 
burners. There is also another opening through the furnace wall to 
allow the gases due to the combustion to escape. Through the bottom 
of the tank, well to the inner side of the furnace, runs the cylinder E. 
Below the bottom of the tank, the cylinder makes a right-angle turn, 
extending through the furnace wall and terminating just outside of the 
wall. The orifice of this cylinder is controlled by gate F. In that 
part of the cylinder that extends upward into the tank, there is an 



10 



No. 109— DIE CASTING 



opening G that allows the molten metal to run into the cylinder from 
the tank. Working in this cylinder, is the piston H. that is used in 
forcing the metal into the dies. The compression lever 7, hinged over 
the inner furnace wall, is kept normally raised by spring pressure, and 
•is connected to the piston by means of the link J. 




Fig. 5. Working Parts of the Soss Die-casting- Maciine 

At the opposite end of the machine from the furnace, is the mechan- 
ism for operating the dies. This mechanism consists of a pair of 
square rods K. upon which are mounted the sleeves L. These sleeves 
have a long bearing surface and are attached to the die-plate M. Lever 
N at the end of the operating mechanism controls the movement of 
these sleeves by means of links 0. Upon these sleeves is mounted a 
secondary set of sleeves P. attached to the other die-plate Q. and whose 



DIE CASTING 11 

movement is controlled by lever R. through links S. This second set 
of sleeves is free to travel with the first set. and in addition has an 
independent movement of its own on the primary sleeves. It is the 
function of lever R to bring die-plate Q up to die-plate M by means 
of links »S' and sleeves P; and it is the function of lever N to bring 
both of the die-plates up to the outlet of the cylinder by means of links 
and sleeves L. This system of sleeve-mounting is one of the dis- 
tinctive patented features of the Soss machine. The orifice of the 
cylinder E is conical in shape and exactly fits the cup-shaped opening 
in die-plate M. so that when the two are brought together, the joint is 
metal tight. At the center of this opening, and extending through the 
die-plate .¥. is an opening that leads to the dies mounted on the inner 
faces of the two die-plates, and a continuation of this opening extends 
through die-plate Q in which the sprue-cutter U works. Attached to 
the outer side of this die-plate are two slotted brackets. In the slot of 
one of these is pivoted the lever T. and in the slot in the opposite 
bracket are bolted two stops that limit the motion of the lever. This 
lever operates the sprue cutter U. that works through the opening in 
die-plate Q. The sprue-cutting mechanism is best shown in Figs. .5 
and 6. At the left of Fig. .5 may be seen a rubber hose connected to 
the air piping. This hose is used for cleaning out the dies after each 
casting operation. 

Operation of the Die-casting- Machine 

The metal for the die-casting machine is mixed in the proper pro- 
poTtions for the work in hand by means of a separate furnace, before 
being poured into the tank of the machine itself. The burners are 
lighted and the dies are set up on the two die-plates. As soon as the 
machine has "warmed up." so that the metal is in a thoroughly melted 
condition, the sprue-cutting lever T is thrown back, leaving a clear 
passageway to the die cavities. Lever R is pulled backward, thus 
bringing die-plate Q up to die-plate M, which operation closes the two 
halves of the die. Then lever N is thrown forward, thereby bringing 
the closed die up to the body of the machine, with the nozzle in close 
contact with the outlet of the cylinder. Next, the gate F is opened, and 
the man at the compression lever I gives the lever a quick, hard pull, 
forcing the metal in the cylinder downward and into the dies. The 
molten metal literally "squirts" into the dies. Gate F is now closed; 
lever X is pulled back to remove the dies from the cylinder outlet; and 
the sprue-cutting lever T is pushed forward, cutting off the sprue and 
pushing it out of the nozzle into the kettle placed beneath it. The 
lever R is pushed forward, an:l a finished casting is ejected from the 
dies. 

An important advantage that this machine has over other die-casting 
machines is the fact that the metal for the castings is taken from the 
Lottom of the melting pot. whereas most other machines use metal fron?, 
the top of the tank. At the bottom of the tank the metal is always the 
best, as it is free from impurities and dross; hence, there is little 
chance for the formation of blow-holes. A handful of rosin thrown into 



12 



No. 109— DIE CAS'fiNG 




DIE CASTING 13 

the melting tank occasionally helps to keep the metal clean, but the 
metal nearest the surface always contains more or less foreign matter. 
While this description of the operation of the die-casting machine 
may convey the idea that the process is a slow one, as a matter ol 
fact, the time required is, on the average, not over a minute and a half 
for turning out a finished casting. With the ejection of the casting 
from the dies, the product is completed, in theory; but in practice there 
are always a few small thin fins, caused by the air vents or by im- 
properly fitted portions of the dies. It is, however, but the work of a 
few seconds to break off these fins, and unless there are many of them, 
or they are excessively thick, they are detrimental neither to the qual- 
ity nor the quantity of finished castings. 

Points on the Operation of the Die-casting- Machine 

We have now taken up the description and general operation of the 
die-casting machine, but like every other machine, there are numerous 
little kinds and practices in its working the observing of which makes 
the difference between good and poor die-casting. Some of these points 
are here given. 

The casting machine is besj; operated by three men, one of whom 
attends to the compression lever and the metal supply in the tank. The 
other two men stand on each side of the die-end of the machine, and 
it is their duty to operate the sprue-cutter, open the dies and remove 
the finished casting, clean the dies with air and close them, throw back 
the die-plates to their casting position over the cylinder outlet, and do 
any other work incident to the operation of the machine. While it 
requires three men to operate a die-casting machine in the best manner, 
the man who attends to the compression lever has a good deal of spare 
time between strokes, and if two or even three of the machines are 
conveniently placed, one man can easily pull levers for all three. 

The metal should be kept just above the melting point and at a 
uniform temperature. If the metal is worked too cold, the result will 
manifest itself in castings that are full of seams and creases, and it 
will be difficult to "fill" the thin places in the dies. If, on the other 
hand the metal is allowed to get too hot, the die will tbrow exces- 
sively long fins, the castings will not cool as quickly in the die. and 
consequently they cannot be made as rapidly. On account of the im- 
portance of keeping the metal at a uniform heat, the fresh metal that 
is added to that in the tank from time to time, is kept heated in a 
separate furnace. Therefore, when the metal in the tank gets low, the 
new supply does not reduce the temperature of the metal being worked. 
Some casters use a thermometer to indicate the heat of the metal. 

Casting-dies require luorication frequently. Just how often they 
should be lubricated depends on the shape of the die, the composition 
of the casting metal, and the general performance of the dies. Bees- 
wax is the common lubricant, and the lubrication consists in merely 
rubbing the cake over the surfaces of the dies that come in contact 
with the casting metal. In die-casting large parts, the dies must be 
kept cool by some artificial means, for hot dies are conducive to slow 



14 No. 109— DIE CASTING 

work and poor castings. To reach this end, large dies are sometimes 
drilled and piped so that water may be circulated through them to 
keep them cool. 

In the Soss machine, the burners are so placed that the metal in the 
cylinder is kept at a slightly higher heat than that in the tank proper. 
This condition is brought about by having the cylinder directly over 
the burners. The value of this feature lies in the fact that gas is not 
wasted in heating the entire tank full of metal to this higher heat, but 
still the metal under compression is at the required temperature. The 
gas consumption of the average die-casting machine is about 100 cubic 
feet per hour. 

The speed at which die-castings may be produced varies with the size 
of the castings being made, the composition of the metal being cast, 
and the style of dies that must be employed. In many cases, in die- 
casting, separate brass or steel pieces are used, that must be placed in the 
dies before each operation so that they will be inserted in and become 
a part of the finished casting. The dies may be diflB.cult of operation 
on account of draft problems or pins and screws that must be inserted 
in the dies and removed from each casting before another can be made. 
These different types of dies will be more fully described in the next 
chapter. Taken as a whole, from ten to sixty pieces per hour are 
the maximum limits for speed in die-casting, and with a well-working 
die, of simple construction, a speed of forty pieces per hour is con- 
sidered good production. It is possible, however, when the castings 
to be produced are small in size and simple in shape, to gate a number 
of them together, or rather to construct the dies so that six or more 
castings may be made at once. By this means it is often possible 
to cast five or six thousand pieces per day of ten hours, on a hand 
die-casting machine. 



CHAPTER II 

MAKING DIES FOR DIE-CASTING MACHINES 

The making of casting dies calls for ingenuity and skill of the 
highest order on the part of the die-maker. There is probably no class 
of die-making in which the work produced is more faithful to the dies, 
both in showing up the little details in the making that reflect credit 
on the dies, and in exposing the defects and shortcomings in the work- 
manship, if there be any. The castings from casting-dies or molds as 
they are sometimes called, may be produced in dimensions down to 
ten-thousandths for accuracy if necesasry. and once the dies are made 
the castings will not vary in the slightest degree, if the working con- 
ditions are kept uniform. 

In spite of the close work required in making casting-dies, the work 
is very .fascinating. Perhaps it is on account of this accuracy; possibly 
it is on account of the fact that they are made from machine steel; 
but most likely -i't is because there are no hardening troubles to be 
contended with. Another factor that makes the work interesting is the 
ingenuity required in the work, for almost every die-maker, if he is 
worthy of the name, likes to figure out and plan for the best way of 
building a die for a difficult job. 

General Principles of Casting--die Making- 
Casting-dies, or molds, have little in common with sand molds. It 
is true that the dies for die-casting are composed of two parts corre- 
sponding to the cope and nowel of the sand mold, but they are so 
different in every other way that no benefit would result from a com- 
parison. 

Generally speaking, casting-dies are made of machine steel; the parts 
which are exceptions are the heavy bases and frames, which are made 
of cast iron, and the dowel pins and small cores, usually made of tool 
steel. Except in rare instances, there are no hardened parts about a 
casting-die; this is the case because the melting points of some of the 
alloys that are die-cast are high enough to draw the temper from any 
hardened parts of the dies. 

The ideal die is simple in construction, with as few parts as practi- 
cable; the castings should be easily ejected and should come from the 
dies as nearly free from fins as possible. To meet these requirements 
in the best way is the proposition that confronts the ingenuity of the 
die-maker. As the die is primarily in two parts, there must be a 
parting line on the casting. This line is always placed at the point 
that will permit the casting to be ejected from the dies in the easiest 
manner possible, bearing in mind the effect the joint will have on the 
appearance of the finished casting; this is a point far less important 
than with sand casting, for, if the dies are properly made this seam will 
be barely perceptible. When it is practicable to do so, it is wise to have 
the parting line come on an edge of the die-casting. Draft is uuneees- 



16 



No. 109— DIE CA§TING 




sary on the straight "up-and-down" places, but of course it is impossible 
to draw any parts that are undercut. Means must be provided for 
ejecting the casting from the dies after completion and it is usually 
done by means of ejector pins, though frequently it is better to have 
the bottom of the die or some other section movable and do the ejecting 
on the same principle that is used on drawing dies of the compound 
type. On close work, shrinkage plays an important part, and the amount 
of shrinkage varies from 0.002 to 0.007 of an inch per inch. Aluminum 
shrinks the greatest amount, Parsons white brass shrinks considerably. 

while tin shrinks but little. 
Thus, it may be easily seen 
that to figure the shrinkage 
allowance for an alloy that 
contains three or four metals 
with different shrinkages, 
requires judgment. To pre- 
vent the air from "pocket- 
ing," air vents are necessary 
at frequent intervals around 
the die-cavity. These vents 
are made by milling a flat 
shallow cut from the die- 
cavity across the face of the 

Fig. 7. Disk cast in Simple Castingr-die ^jj^ ^^ jj^g OUtside edges of 

the block. From y^ inch to % inch is the usual width and from 0.003 
to 0.005 of an inch, the customary depth, varying with the size and 
shape of the die in question. 

The dies ot molds for die-casting are of various styles, as are also 
punch-press dies, and it would be difficult to lay down specific rules 
for their classification. There are the plain dies, without complications 
of any kind; slide dies with one or more slides; dies for bearings, both 
of the "half-round" and of the "whole-round" types; dies for gated 
work; and many other less important classes. Then there are dies that 
have features that belong to more than one of these tjT)es, so that it 
is easily seen that to decide upon the style of die that would be best 
for a given piece of work requires a good deal of experience. Some of 
the most important of these types can best be shown by illustrating dies 
made in the various styles, showing, step by step, how the dies are made 
and assembled. To begin with, consider the making of a casting-die 
of the very simplest form. 

In Fig. 7 is shown a plain flat disk made by die-casting. In actual 
practice, a die would not be made for such a simple piece, unless there 
were some features about it that would prevent it being made on a 
screw machine or with press tools. It might have a cam groove cut 
in one of its flat sides, the sides might be covered with scroll work, 
there might be gear teeth around its circumference, or a hundred and 
one other conditions to make die-casting a desirable method of manu- 
facturing. All these complications are omitted for the sake of simpli- 
fying this initial description of a casting-die. 



THE MAKING OF THE DIES 



17 



Fig. 8 shows the die for this piece in plan and sectional elevation. 
A is a square cast-iron frame, made from a single casting. This frame 
or box. as it is generally called, is planed on the top and bottom only. 
Next, the two die-halves B and C are shaped up from machine steel. 
In this casting-die, and in the majority of others, these die blocks are 



c 





Machinery, !f.Y. 



Fig-. 8. Simple Casting-die for Casting BlocJi shown in Fig. 7 

square. The lower half of the die B is held to the cast-iron frame by 
fillister head screws, set in counterbOTed holes, thus sinking the screw- 
heads under the surface of the block. The upper half of the die C is 
located upon B by dowel pins driven into B which have a sliding fit in 



18 No. 109— DIE CASTING 

the reamed holes iu C. This being done, the die-half B is fixed to the 
faceplate of the lathe and the recess bored for the die-cavity. This 
operation is a simple one in this case, for it is merely a straight hole 
one-half inch deep and three inches in diameter. Of course this recess 
must be carefully finished with a tool that has been stoned up to a sharp 
edge, using lard oil. Emery cloth should be used as little as possible. 
It is unnecessary to give this hole draft, but it must be free from ridges 
or marks that would prevent the casting from being pushed out. If the 
faces of the dies are spotted with a small piece of box wood or rawhide 
held in the drill press and kept charged with flour emery, the die-cast- 
ing will reproduce this "bird's-eye" finish and the appearance will well 
repay the few minutes additional time that it will take. The spotting 
should be done with dry emery (without oil) to get the brightest finish. 
The upper die-half C is simply ground on its working face. The outside 
corners and edges of the faces of both die-halves should be well rounded 
off so as to insure the absence of slight dents or rough places that 
might prevent the dies from fitting perfectly. 

The ejecting mechanism must next be considered. Lever D. pivoted 
from bracket E, has a steel pin F that engages in the elongated hole 
in bracket G. so that an upward pull of the lever D raises bracket G, 
which is attached to ejector-pin plate H. This plate is a loose fit over 
the guide screws I that are attached to the lower die-half B. The 
ejector pins J, four in number, in this die, are riveted into the ejector- 
pin plate, and they work through holes drilled and Teamed through the 
lower die-half. The ends of these pins must be finished off so as to lie 
perfectly flush with the inside of the die when ready for operation and, 
of course, they must be a sliding fit in the holes in the die. 
^ An important feature of a casting-die is the sprue cutter, shown in 
this die at K. If the disk for which this die was made, had had a hole 
or central opening of any kind, the sprue cutter would best be operated 
at that point; but, as this disk is plain, the sprue cutter must be placed 
at the edge. At the outside of the die-cavity, as shown in Fig. 8, the 
opening for the sprue cutter is laid out, drilled and filed to shape. 
It is obvious that the side of the sprue cutter adjacent to the die must 
fit the outline of the die perfectly, so that there will be no break in 
the appearance of the casting. The opening for it is extended through 
the upper die-half, and from a point % of an inch from the inside face 
of the die this hole is fiared out nearly as large as the opening through 
the die-plate of the machine. Of course the apperture in the upper die- 
half must be no larger than the opening through the die-plate; other- 
wise the sprue could not he pushed out. The sprue cutter itself is a 
long rod. whose section is of the same shape and size as the openings 
just made, and it is connected to the sprue cutting mechanism of the 
machine. Of course it is unnecessary to shape the entire length of 
the sprue cutter to size; after the working end is milled to shape for a 
distance of six or eight inches, the rest of the rod may be left round. 
The sprue cutter is finished first, after which both the openings in the 
die are fitted to it; and while the fit should he metal tight, it must be 
perfectly free to slide. 



THE MAKING OF THE DIES 19 

The dies are mounted on the die-plates of the casting machine by 
means of straps, much the same as bolsters are held on punch press 
Deds. The position of the die on the die-plate must be such that the 
opening for the sprue cutter will line up with the nozzle at the outlet 
of the cylinder. At the time of casting, the position of the sprue cutter 
is as shown in the illustration of this die, Fig. 8. In this position there 
is room for the metal to enter the die-cavity, and yet there is but a 
small amount of metal to be cut off and pushed back after the die has 
been filled with metal. 

With slight modifications, the above style of die may be used for die- 
casting any piece that will draw or pull out of a two-part die. If holes 
must be cast through the piece, it is only necessary to add core pins to 
the lower die B, a point that will be more fully described later. It is 
unnecessary to add that both halves of the die may be utilized in 
making the cavity for the die, should they be needed. Also, it is often 
easier to machine out the recess larger than is needed, and set in 
pieces in which parts of the outline of the die-casting have been formed. 
Gear teeth are put in the die in this way; a broach is cut similar to the 
gear desired, then hardened and driven through a piece of steel plate 
which is afterward fitted to its place in the die. 

Slide Dies 

The die illustrated in Fig. 9 is one of the most successful of the 
various types of casting-dies, and if properly made is an interesting 
piece of die work. The prinicpal use of this particular style of die, 
called a slide die, is to cast parts like the one shown in Fig. 10, which, 
is a disk similar to the one which the last die described was to cast, 
except that it has raised letters at the edge and a hole in the center. 
It is obvious that the die last described, (Fig. 8), would not do for 
disks or other pieces having projections or depressions around their 
edges, as, for instance, printing or counting wheels with raised or 
sunken characters, or grooved pulleys. Briefly, this style of die is 
similar to the simple casting-die, except that slides are provided, to the 
required number, which form the edge of the casting. A die for a 'plain 
grooved pulley would require but two slides, while a die for a printing 
wheel with forty letters around its edge would necessitate forty slides, 
one for each of the letters. The die about to be described, shown in 
Fig. 9, was made to cast a wheel with six iraised letters. 

Referring to Fig. 9, D is the cast-iron box or frame, E, the lower die, 
and F the upper die. In making the lower die-half, the stock is first 
shaped to size and doweled to the blank for the upper die-half, and the 
holes for attaching to the frame are drilled. For the sake of clearness, 
these holes and screws are omitted from the illustration as are also 
the vents, since they have been fully explained. The lower die is next 
strapped to a face plate, trued up, and bored out nearly to the diameter 
of the body of the piece to he cast, exclusive of the raised letters. The 
depth of this recess is equal to the thickness of the printing wheel plus 
3/16 inch to allow for the cam ring G that is used to reciprocate the 
slides of the die. The cam ring is made large enough to cover the die- 



20 



No. 109— DIE CASTING 



cavity as well as the slides that surround it, with an allowance of an 
inch or two for the cam slots H. The six slides / are made long enough 
to have good bearing surfaces. With the size of the cam ring deter- 
mined, the die is next bored out to receive this cam ring and the last 
inch of the recess is carried down to the depth of the die cavity so as 
to make an ending space for the slots that the slides are to work in. 




SECTION ABO 




Maehineru,N. Y. 



Fig. 9. Slide Die lor Casting- the Printing- "Wheel sbo-wn In Fig. lO 

The die is now taken from the faceplate and the slots for the slides 
laid out. 

These slots may be milled or shaped, but milling is to be preferred. 
The next step is the making and fitting of the slides, which are of 
machine steel, having a good sliding fit in the slots. The six slides are 
fitted in position and left with the ends projecting into the die proper. 



THE MAKING OF THE DIES 



21 



The slots H are next profiled in the cam ring G. and the pins / that 
■work in them are made and driven into the holes in the slides. With 
the slides and cam ring in place, the cam ring lis rotated to bring all 
the slides to their inner position where they are held temporarily by 
means of the cam ring and temporary screws. The die-half with the 
slides thus clamped in the inner or closed position, is set up on the 
lathe faceplate and the die-cavity indicated up and bored out to the 
finish size, which operation also finishes the ends of the slides to the 
proper radius. The die may now be taken down and the slides removed 
to engrave the letters upon their concave ends. The engraving can be 
done in the best manner on a Gorton engraving machine, but if such a 
machine is not available they may be cut in by hand. Stamping should 
never be resorted to for putting in the letters, because the stock dis- 
placement would be so great that it would be impossible to refinish the 
surface to its original condition. Before fitting the cam ring, an open- 
ing must be milled in the 
die to allow the handle to 
be rotated the short distance 
necessary. After the cam 
ring has been fitted, it is 
held in by the four small 
straps K. attached by screws 
to the lower die-half at the 
corners. 

The sprue cutter, which is 
not shown, is operated 
through the hole in the 
center of the piece and is, 
of course, round in this 

Fig. ID. Printing Wheel cast in a Slide Die ^jg Its action is the Same 

as was the one previously described, and the ejecting device 
is similar, with the exception that the brackets L that are attached to 
the ejector-pin plate M, are widely separated so as to make room for the 
sprue cutter that works through a hole in the plate M. 

Die for Casting with Inserted Pieces 

For making die-castings that are to have pieces of another metal 
inserted, it is necessary to have a die With provisions for receiving the 
metal blank and holding it firmly in position while the metal is being 
cast around it, and of course the piece must be held in such a manner 
that it can be easily withdrawn from the die with the finished casting. 

The die illustrated in Fig. 11 is for a part that is used as a swinging 
weight, shown in Fig. 12. The upper part of the piece is made from a 
sheet steel punching, so as to lighten this part of the piece as well as 
to give increased strength, especially at the hole at the pivoted end of 
the work. The cast portion of the piece is slotted lengthwise, as the 
•illustration shows; and three holes pass through the casting, piercing 
the sides of the slot. In addition to showing the method of making dies 
for Inserted pieces, this die shows the principles of simple coring. 




22 No. 109— DIE CASTING 

In making this die, two machine-steel blanks are planed up for the 
?ipper and lower halves of the die, A and B, the lower die being made 
nearly twice as thick as the upper die because it is in this part that 
ihe most of the die-cavity will be made. In this lower half of the die 




K^ 



J V 




o 



TlaShinery.V.'i. 



Fig. 1 1 . Casting-die for Making- Castings -with Inserted Pieces like 
that shown in Fig. 12 

the stock is milled out to the same shape as the outline of the plan 
view of the casting, being carried down to the exact depth of the thick- 
ness of the casting. From the wide end of this recess the stock is 
milled or shaped out in a parallel slot to the outside of the die-block. 



THE MAKING OP THE DIES 



23 



At the bottom of the side of this wide slot are T-slots to guide the 
slide E that is to work in this opening. The side is milled and fitted 
to the T-slots and opening in the die, but is left considerably longer 
than the finish size. Next, the slide is mounted on the faceplate of a 
lathe and turned out on the end with the proper radius and a tongue 
to form the slot that is to be in the curved end of the casting. At the 
outer end of the slide is left a lug that is drilled and tapped for the 
operating lever F that reciprocates the slide, using the stud in bracket 
K as a fulcrum. 

Two pieces of machine steel are next shaped and finished up to 
form the chamfered part of the casting and to locate the inserted steel 
punching in the die. The combined thickness of these pieces C and D 
is equal to the thickness of the casting, less the thickness of the in- 
serted piece. It is now an easy 
matter to seat section D in the 
bottom of the milled part of the 
lower die-half, and to locate 
section C in its proper position 
on the upper half. A pilot pin 
M is fitted in D to hold the 
steel punching in position by 
means of the hole that is in the 
extreme upper end of the 
punching. The pilot pin extends 
through this hole into a cor- 
responding hole in section C. 
At the lower end of the steel 
part that is inserted, there are 
two holes the object of which is to secure the punching to the die- 
casting, for the molten metal runs through these holes, practically 
riveting the die-casting to the inserted piece. 

Provision has now been made for holding the sheet-metal part that is 
10 be inserted, and the cavity has been completed for the casting, in- 
cluding the tongue at the end; it now remains to describe the manner 
of forming the holes that pierce the casting through the slotted por- 
tion. In the lower die-half the positions of the three holes H are 
laid out, drilled and reamed. Then, with the two die-halves together 
?ni the slide clamped at its inner position, the holes are transferred 
through the slide and the upper die. This being done, it is an easy 
-natter to make core pins and drive them into the upper die at the two 
end holes, the center hole being taken care of by the sprue cutter L 
that will be described later. The core pins should be a nice sliding fit 
through ;^he slide and in the holes in the lower die, into which they 
should extend from a quarter to half an inch. In addition to coring 
the holes, these pins act as a lock to hold the slide L' in its proper 
position at the time of casting. 

The sprue cutter L is most conveniently operated in the center 
hole, thus doing away with the core pin that would otherwise be re- 
quired. The sprue cutter needs little description in this die, for as in 




Fig-. 12. 



Die-cast Weierht -with Inserted 
Sheet-steel Punching 



24 



No. 109— DIE CASTtNG 



the slide die, It is merely a plain round rod that fits closely in the 
holes through the dies and slide. The ejector mechanism is the same 
in this die as in the dies already described; therefore further descrip- 
tion is unnecessary. 



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Machinery, N. Y, 



Fig. 13. Oastingr-die for the Halt-round Bearing: shown In Fig. 14 

The operation of this die is very simple. The sheet-steel piece is 
laid in the recess in the open die. being located by the pin M. Slide 
E is thrown in by means of lever F. and the dies are closed. At the 



THE MAKING OF THE DIES 



25 



time of casting, the sprue cutter in is the position shown in the sketch, 
being nearly through the die-cavity. As before explained, this 
position admits the molten metal to pass into the die-cavity, but still 
leaves very little sprue to be cut off after the die-casting is completed. 
It should be stated that the steel piece that is inserted must be per- 
fectly flat and free from burrs that would prevent the die-halves from 
coming together properly. 

Bearing Dies 

Bearing dies are one of the most important of the various classes of 
casting-dies. The bearings produced by die-casting are so far superior 
to those made by other casting methods and machining that their use 
is now very extensive. Dies are made for "half-round" and "whole- 
round" bearings. There is little out of the ordinary about a whole- 
round die. but the half-round die involves many interesting methods 
of die-making, and for that reason is here described. 

Fig. 13 shows a casting-die for half-round bearings. Half-round bear- 
ing dies are usually made to cast two bearings at a time, for the 
reason that it is just as easy to cast two pieces of such a shape as it 
is to cast one, and, in addition, the die is balanced in a better manner. 
As with other dies, the first step is to machine up the frame A and the 





- 




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f-\ 


/ x'' ^^^A-727'l,''' ^N J"^ 






Machinery.N.Y. 



Fig-. 14. Die-cast Half-round Bearing-, Sho-wing the Cast Oil Grooves 

two die-halves B and C. The pieces B and E that are to form the 
insides of the bearings are then turned up and one side of each shaped 
and keyed to fit the slots that have previously been milled in die-half 
C. These parts are held in place by dowels and screws. One of the 
bearings produced by this die is shown in Fig. 14, and it will be 
noticed that there is an oil groove within that covers the length of 
the bearing. To produce this groove in the die-castings, a shell must 
be turned up and bored out whose Inside diameter is that of the inside 
of the bearing, and whose thickness equals the depth of the oil groove. 
This being done, the oil grooves are laid out upon the shell and cut 
out by drilling and filing. After rounding the outside corners, these 
little strips are pinned to the cores D and E in their proper places. 

Another little kink in this connection is worthy of noting. So many 
different styles and sizes of bearings are made by a concern doing much 
die-casting that it is essential that the die-cast bearings should bear 
some distinguishing number to identify them. As this number is of no 
consequence to the user it is well to have the number in an incon- 
spicuous place, but it must be where it will not be effaced by scraping, 
etc. Bearing in mind that it is much easier to produce raised lettering 
by die-casting than to produce sunken lettering, it will be readily seen 



26 



No. 109— DIE CAg*riNG 



that the oil groove affords a good place in which to put the bearing 
numbeir. This is easily done by stamping the figures upon the narrow 
strip that forms the oil groove. In this place on the bearing it may be 
easily found if needed, and of course there is no danger of its being 
taken out by machining. 

The lower die consisis of two blocks F and G, each of which contains 
an impression of a bearing. The best way to make these parts is to 
lay out the ends of each of the blocks with the proper radius, taking 
care to have the center come a little below the surface of the face of 
the block. Then the blocks should be shaped out to get the bulk of the 
stock out. before setting up in the lathe. After the lathe work is done 




Fig. 15. Interesting- Examples of Die-castings 

on each piece, which of course is usually done separately, the faces of 
ihe two blocks are faced down just to the exact center of the impres- 
sion. It will be noticed that two blocks are used for the lower part of 
the die. The reason is to facilitate the locating of the female parts 
of the die in proper relation to the male parts. After properly locat- 
ing, they may be doweled and screwed to baseplate B. 

The sprue cutter H, better shown in the plan view, is square in 
shape and connects with the die-cavities in a thin narrow opening on 
either side of the sprue cutter. The ejector pins, /. two to each die. 
are at the ends of the bearings. The ejector-pin plate J is necessarily 
■•arge, and is operated by lever K. 

Fig. 15 shows a number of interesting examples of die-castings. 



CHAPTER III 



VAN WAGNER MFG. CO.'S DIE-CASTING PRACTICE 

In 1907, Mr. E. B. Van Wagner, of Syracuse. N. Y., established the 
E. B. Van Wagner Mfg. Co. for the production of die-castings. The fac- 
tory comprises the office section, the machine shop where the dies and 
casting machines are built, the metallurgical laboratory where the 
metals are alloyed, the casting department shown in Fig. 17 where the 
die-castings are made, and the trimming department. 

Possibilities and Limitations of Die Casting 

At the outset we may say that it is possible to die-cast almost any 
piece, but it is not by any means practicable to do so. It must be 
remembered that to die-cast on a practical basis the dies must be con- 









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A 








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B 














C 


Tachinery 



Fig. 16. Die-casting- Constructions to be avoided 

structed in such a manner that the cost of their operation and up-keep 
will be light, or there will be no profit in die-casting. It is impractic- 
able to produce under-cut work, that is, work having no draft and 
which is therefore impossible to draw from the die. Such an instance 
is that illustrated at A, Fig. 16, and by the internal section of M, 
Fig 21. and the internal groove in 0, also shown in Fig. 21. If abso- 
lutely necessary, work of this kind can be done by the use of collapsi- 
'rle cores; but here, again, we meet resistance in maintaining the dies 
:n proper condition, and, moreover, this method is commercially im- 
practicable, owing to the difficulty of operating these cores rapidly. 
Hollow work, requiring curved cores, like faucets and bent piping of 
the character illustrated at C in Fig. 16, are difficult to produce. If, 
in designing the piece, it can be planned to have the parts of such a 
shape that the cores can be readily withdrawn, employing a two-piece 
core with a slight draft in each direction, the division coming as indi- 
cated by the core line of C in Fig. 16, the problem becomes simpler. 
Oftentimes this worK can best be done by casting in a straight piece. 



28 



No. 109— DIE CASTING 




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MACHINES AND METHODS 



2^ 



if the threads are fine, say. under twenty-four to the inch, should not 
be die-cast, because under moderate pressure they will strip. A good 
way to treat constructions of tnis kind is to enclose brass or steel 
bushings in the die-castings in which the threads are required. 

As to the accuracy with which die-castings may be produced, it is 
possible to keep dimensions within 0.0005 inch of standard size, but to 
do so requires considerable expense in keeping the dies in condition. 
A limit of 0.002 inch, however, is entirely practicable, and can be main- 
tained easily. In specifying the accuracy with which die-castings are 
to be made, only those parts which are absolutely essential should be 
fteld to size, in order to keep the cost of the work nominal. One of the 
great advantages of the use of die-castings is that no finishing is re- 
quired after the pieces leave the molds. Finish requirements should 
be plainly stated in ordering die-castings, as the alloy must be suited 
to these requirements. 

Another great saving is effected on lettered work, either raised or 
sunken. One of these jobs is illustrated at Q, Fig. 22, which shows an 

































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Figr. 18. Methods of attaching Die-cast Gears, etc., to Shafts 

example of die-cast lettering. Sunken lettering is to be preferred to 
raised lettering, as the latter is more easily injured. Knurled work 
may be produced easily, if straight knurls are used, and threaded sec- 
tions over 1/4 inch in size are entirely practicatble, either internal or 
external. External die cast threads are illustrated at R and S, Fig. 22. 
The casting of gears and segments is a familiar appliction of die- 
casting; this is illustrated by the large gear at N, Fig. 21, and the 
segment at W, Fig. 23, which give an idea of the general character of 
this class of work. The casting of pulleys, gears, and similar parts on 
shafts may be easily effected as shown by the gear on the shaft at N, 
in Fig. 21. The views shown in Fig. 18 are intended to convey an 
idea of three methods of die-casting around shafts. At D is shown a 
die-casting cast around a steel shaft. If the surface of the shaft 
coming within the pulley has been previously knurled, the pulley will 
grip it much better, but for ordinary purposes the shrinkage of the 
die-cast metal around the shaft is sjifficient. If any heavy strain is to 



30 No. 109— DIE CAS'fiNG 

be imposed on the work, it is better to provide anchor holes through 
the shaft, liKe those indicated at E. It will be readily seen that the 
die-cast metal runs through these holes in the shaft, forming rivets 
which are integral with the casting. For locating levers upon the ends 
of shafts, etc., a good way is to flatten opposite sides of the shaft and 
east around them, as shown at F, Fig. 18. The screw seen projecting 
beneath the piece at Q. Fig. 22, was die-cast in place. Any of these 




Fig. 19. A Few Poaaibnities of Die Casting: 

methods are to be recommended, and a proper knowledge of possibili- 
ties of this kind will increase the scope of die-casting. 

Another phase of die-casting which can well be borne in mind is 
the possibility of inserting steel or other parts in the die-casting. Such 
an instance is shown at G in Fig. 19— a die-casting which was made, 
by the Van Wagner Co. as a part of an electrical apparatus, the steel 
insercs being contact points. Oftentimes it is found advisable to in- 
clude brass bearing rings to give additional durability at points where 
the die-cast metal would not stand up. The die-casting shown at U, 

















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Fig. 20. Castings -which iUuatrate Points of Shrinkage and Draft 

Fig. 23, in which the brass ring at T has been incorporated, is typical 
of such cases. To die-cast pieces like those shown at H in Fig. 19, and 
similarly at V in Fig. 23, having inverted conical openings, might at 
flrst thought seem difRcult, but this is entirely practicable. Similarly, 
split bushings like those shown at I. Fig. 19. and at W. Fig. 23. may 
be cast with projecting lugs for the reception of screws for clamping 
upon shafts, etc., but this construction should not be used if frequent 
tightening or loosening will be necessary. 

The shrinkage problem mainifests itself in die-casting in the same 
measure that it does in other casting operations. Different metals 



MACHINES AND METHODS 



31 



shrink in different degrees, as will be explained later on. However, one 
important point can be mentioned at this time: that is, the amount of 
shrinkage is often dependent upon the shape of the piece. For in- 




Fig. 21. Die-castings showing- Impractical Under-cut Sections; also a 
Large Gear die-cast on Shaft 

Stance, pieces like those shown at E in Fig. 20 or at X in Fig. 24, will 
shrink very little on account of the fact tnat the steel mold is of such 
shape that the central core will prevent the die-casting from shrink- 




Fig-. 22. Die-castings which show Lettering and Thread Castings 

ing. However, pieces like those shown at L in Fig. 20, or at V in Fig. 
24. which have nothing to hold them from pulling together as they 
cool, will shrink to the greatest extent. All of these points must be 
taken into consideration when designing work for die-casting. Prac- 
tically no draft is necessary on a die-casting, except on very deep sec- 



32 



No. 109— DIE CASING 



tions, as indicated at J in Fig. 20, where a draft of 0.001 inch to the 
inch is desirable. Perfectly straight sections, however, can be cast, 
as the shrinkage of the metal is usually enough to free it from the 
die. 




Pig. 23. Typical Die-castings illustrating- Various Points 

It is the opinion of the Van Wagner Co. that die-casting costs can be 
materially reduced if designers will bear this point In mind when 
cringing out new designs. Even though it is often possible to cast 
special pieces, incorporating several parts in one, and thereby accom- 
plishing what seems to be a great stunt to the designer, it is some- 
times more practicable to make the piece in several sections and later 




Fig. 24. Die-castiu^s illustrating the Extremes of Shrinkage 

assemble it. Not only is this simpler for the die caster, but it is also 
more economical for the customer. Such points as avoiding thin sec- 
tions, including large fillets at corners, as well as taking account of 
the under-cut problem, are simply matters of common sense, but they 
can profitably be considered by the designer. 

The Van Wag-ner Die-casting- Machine 
The first essential to good die-casting is a good casting machine. 
Perhaps the best known types of casting machines are of the familiar 



MACHINES AND METHODS 



33 



plunger type, of which there are several varieties, the pneumatic type 
and the rotary or automatic type. (For descriptions of various types of 
die-casting machines, see "Die Casting Machines," Machixery's Refer- 
ence Book No. 108.) For the economical production of die-castings, 
however, the hand-operated machines are rather too slow, and auto- 
matic machines are applicable only to a class of work which may be 
made in very large quantities. For these reasons, therefore, the Van 
Wagner Co. employs the compressed air type of die-casting machine 
which was patented by Mr. E. B. Van Wagner in 1907. In the casting 
department of the Van Wagner shop, illustrated in Fig. 17, there are 
installed about thirty machines. Fig. 27 shows a die-casting 




Machinery 



Fig. 25. Drawing illustrating Principle of Van "Wagrner Die- 
castingr Machine 

machine in the open position. Fig. 26 shows a closer view of the die- 
operating mechanism and Fig. 25 is presented to give a general idea 
of the construction of the entire machine. 

By referring to the line illustration Fig. 25, which shows the Van 
Wagner pneumatic die-casting machine in part, and comparing this 
illustration with Fig. 26, which shows the general appearance of the 
die-operating and other mechanism of the casting machine, a good idea 
may be obtained of its construction and working. At A may be seen 
the base of the machine in which is located the melting pot B. This 
melting pot is heated by means of fuel oil passing through the supply 
pipe C to the burners Cj. A vent pipe D is provided to take away the 
gases incident to combustion. The pressure for "shooting" the metal 
into the die cavity is supplied by air through the supply pipe E. A 
valve controls this air supply. The pressure is regulated to suit the 
particular casting or die, the proper amount being determined by ex- 
periment. Similarly, an air exhaust pipe F. which may be seen 
directly above the supply pipe, sub-divides into two tubes which ex- 



34 



No. 109— DIE CASTING 



tend to the die cavity to exhaust the air before the metal is ad- 
mitted. There are two methods of overcoming the presence of air in 
the die cavity — the exhaust method and the venting method, and it is 
the former that is here describpd. 




Fig. 26. View o{ Machine showing Die-operating- Mechanism 

A "goose-neck" G. shovk^n in Fig. 25, serves to temporarily contain 
the metal which is forced into the mold. An amount of metal 
slightly in excess of that required for one die-casting is placed in this 
goose-neck with a hand-ladle, previous to each operation of the machine. 
One end of the goose-neck is connected to the air pipe, E. while the 
other end terminates in the nozzle G^. This nozzle may best be seen 
by referring to the illustration of the machine shown in Fig. 27, in 
connection with Fig. 2.j. One of the advantages in using this goose- 



MACHINES AND METHODS 



35 



neck is that the entire air pressure is expended upon the metal in the 
goose-neck, and, by reason of its isolated position, the goose-neck and its 
contents are kept slightly hotter than the contents of the melting pot. 

The Die-operating' Mechanism 
The die-operating mechanism of the machine is contained within 
a hinged framework, shown in position for the removal of the die- 
casting in Fig. 27. Referring to Fig. 26, in connection with the line 
illustration Fig. 25, it will he seen that the die-holding mechanism is 
all supported upon the lower die-holding plate H, which is hinged to 
the edge of the base of the machine. A lock J serves to hold the dies 
and operating mechanism in the upright operating position, and by 
means of a counterbalance, suspended from an overhead rope which 
connects with the top of the mechanism at P, the changing of the posi- 




Fig. 27. Die-casting Machine in Position for Removal of Casting: 

tion of this mechanism is easily effected, and when thrown into the 
horizontal position, as indicated in Fig. 27, it rests upon a support 
while the dies are being opened and the castings ejected. 

The lower die is shown at H^, and the upper die TT, is mounted upon 
the upper die-holding plate E. Four rods L act as guiding members 
for the upper die-holding plate to slide upon. These rods L are mounted 
in fixed positions at the corners of the lower die-holding plate H. and 
at their upper ends the operating shaft supporting plate M is located 
in a fixed position, serving to support the upper ends of these rods. 
The position of this plate 21 is adjustable upon the rods by means of 
check-nuts, thus providing for the accommodation of thick as well as 
thin dies. A shaft is supported in this top plate, and by means of 
the operating lever :\' working through slotted levers 0^, and links O^, 
the upper die-holding plate and die can thus be removed from contact 
with the lower die at will. 

The metal enters the die cavity through the nozzle G^, and after 
setting, it is necessary to cut the sprue formed by the surplus metal that 



36 



No. 109— DIE CASTING 



remains outside the die cavity. For this purpose, a sprue-cutter, 
operated by means of liand-lever Qu is employed. This sprue-cutting 
lever is hinged in the fulcrumed link Q,, and is held in its casting posi- 
tion by means of an adjustable stop on bracket Qg. 

In many dies, it is necessary that water be circulated through the die- 
blocks to keep them cool during the die-casting operation. In Fig. 26, 
the water pipe may be seen at R, and hose pipes run from this supply 
to each side of the die-blocks, thus providing a cooling circulation. In 
this illustration, the pipes used for exhausting the air from the die 
cavity are apt to be confused with the cooling pipes, but by following 




Flgr. 28. General View of Trimming Department 

the two pipes leading veriicauy down to the machine, the exhaust pipes 
may be seen and kept distinct from the water pipes. 

Making- a Die- casting- 
In order to clearly understand the operation of the die-casting ma- 
chine, let us follow the sequence of events that takes place in producing 
a casting. Two men are required to operate the machine. In Fig. 27. 
the operators may be seen in their working positions. The first step 
is taken by the operator at the left who, with a hand-ladle, dips enough 
metal for one casting from the melting pot and pours it through nozzle 
Gi into the goose-neck. The second operator in the meantime is replac- 
ing the cores in the dies, adjusting the position of the sprue-cutter and 
closing the dies preparatory to making a casting. This being done, he 
elevates the dies and their operating mechanism, which are hinged and 
counterbalanced, as previously described, bringing them to an upright 
position. The die operator now mounts the box, raises the sprue-cutter 
to its open position to admit the metal; after which the machine opera- 



MACHINES AND METHODS 



37 



tor turns the air valve with his left hand.' The operation of this air 
valve admits the air behind the metal, forcing it into the die, and the 
same movement opens the exhaust valve slightly in advance. The 
exhaust valve is located upon the second length of piping just above 
the air valve, and as a link connects the two valves, the single motion 
exhausts the air from the die cavity and immediately afterward the air 
is admitted behind the metal, thereby "shooting" the metal into the die. 
This being done, the air is shut off and the die operator cuts the sprue 
by means of lever Q^, withdraws the cores in the die, throws the dies 
to the open position (which is indicated in Fig. 27), and operates the 
ejecting mechanism, thus removing the casting from the die. In the 
meantime, the machine operator is tending to his metal supply and 
getting a ladle full of metal ready for the next die-casting operation. 
By referring to the machines shown in Fig. 17, it will be noticed that 




Fig. 20. Trimming Die-castings on a FUing Machine 

only a few are provided with exhaust piping for venting the dies. 
Another venting method will be described later. 

The number of die-castings which can be made on one machine per 
day of ten hours varies with the character of the pieces being die-cast, 
the number of pieces made at each operation of the machine and the 
ease with which the dies may be worked, which depends, of course, 
upon the number of cores and parts to be handled at each die-casting 
operation. The dies shown in the machine in Fig. 26, produce four 
bearings at each operation. 

Trimming^ Die-castingrs 

At the end of each run the operators of the machines go over their 
work, breaking the castings from the sprues and throwing out all that 
are defective. No matter how carefully the die-casting molds have been 
made, there is always a certain amount of trimming to be done on the 
finished die-castings, on account of the crevices left in the die for air 



38 



No. 109— DIE CASTING 




MACHINES AND METHODS 3& 

vents, or which exist from improper fitting of the parts of the dies. 
These "fins," as they are called, are trimmed by hand operators in a 
special department. A general view of this trimming room is shown 
in Fig. 28. Usually it is sufficient to scrape these fins off with a scraping 
knife, but if the casting is especially difficult to produce, so that a large 
opening is required to admit the metal, it is sometimes necessary to 




Fig:. 31. A Typical Die-casting Mold 

trim unusually thick sprue sections by filing. Fig. 29 illustrates the 
method of trimming such die-castings on a filing machine. 

The Dies Used 

Next to the casting machine, the dies or molds are the most impor- 
tant necessary factor. A general view of the Van Wagner Co.'s die- 
making department is shown in Fig. 30. In order to gain a proper 
conception of the work required in producing a high-grade die-casting 
mold, we will follow the different steps which are necessary in making 
the mold. The first and most important step is the proper planning of 
the die. Before any work at all can be done, it is necessary to plan the 



40 



No. 109— DIE CASTING 



die. i. e., to decide just where tlie parting lines will come; just what 
method will he used for ejecting the piece; what alloy will be used; 
where the casting will be gated; and a hundred and one minor points, 
all of which have a direct bearing upon the performance of the finished 
dies. All these decisions have to be made by the diemaker. and in Fig. 
37 he is shown, micrometer in hand, computing the shrinkage allow- 
ances that he will make in the dies. This is a very important factor on 
accurate work as the shrinkage varies from 0.001 to 0.004 inch, accord- 
ing to the alloy and the general shape of the piece. 

Before taking up the actual machining operations of the mold-making 
as conducted in this factory, it will be well to take a typical die-casting 
mold and note its general construction. Fig. 31 shows a typical die- 
casting mold closed, while Fig. 32 shows the same mold disassembled on 



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Fig:. 32. Die-casting' Mold sho'wn in Figr. 31, disassembled 

the bench to show its construction. The piece for which the mold has 
been made is also shown. Fig. 33 shows a similar die in section. From 
the three illustrations a good idea of an average die-casting mold can 
be obtained. Referring to these illustrations, the principal parts of this 
die are the ejector box A, and the ejector plate B which is operated by 
the racks C. For operating the ejector plate, the pinion shaft D having 
a handle suitable for turning, is furnished. This, of course, fits into a 
bored hole in the ejector box, bringing the pinion into mesh with the 
racks for raising the ejector plate. In the ejector plate are three ejector 
pins E for removing the casting from the mold. The ejector pins 
operate through holes F. Beyond the pinion shaft may be seen the 
casting for which this mold has been made. It will be noticed that 
the top side of the casting has three projecting lugs through which are 
small holes. Provision for forming this side of the die-casting is made 
in the lower half of the mold G. while the upper half of the die-casting 



MACHINES AND METHODS 



41 



lOi 



is taken care of by the top plate H. One of the toggles for operating the 
core pins through these three lugs is shown at I. These parts will be 
described more fully later. The sprue cutter is shown in position in 
the die at J. 

Machiningr the Die Cavities 

As will be noticed from Fig. 30, the machinery in the die-making 
department is of modern design, for no other class of work demands as 
good tool equipment and as much skill in the making as die-casting 
molds. The die-blocks are made of machinery steel. Fig. 34 illustrates 

the first step in making a 
die-casting mold after the 
die-block has been shaped 
approximately to size. This 
operation consists in care- 
fully facing off the die sur- 
faces on a vertical-spindle 
grinding machine. This, of 
course, is a quick method of 
surfacing the die-block, and 
it insures that the top and 
bottom surfaces of these 
plates will be parallel, per- 
mitting the die-faces to come 
together properly. 

The next step consists of 
laying out the die, as shown 
in Fig. 36. This is done in 
the usual manner, by work- 
ing on a coppered surface, 
using dividers, scales, and a 
center punch. When laying 
out the die, the necessary 
allowances are made for 
shrinkage and finish, these 
points having been planned 
before actual work on the 
die has been started. As in 
other phases of die-work, 
the machining operations 
are performed, as far as pos- 
Fig-. 33. Section tiirough a Die-casting Mold sible before any hand-work 
is done. In Fig. 38 may be seen a die-maker turning the cavity in a 
part of the die-casting mold. The highest type of skilled workman- 
ship is called for on this machine work, and as may be surmised from 
Fig. 38, where the die-maker is shown measuring the die with a vernier 
caliper, the measurements must be exact, for no grinding operations 
follow the machine work. 



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'Machinery 



42 



No. 109— DIE CASTING 



Figs. 35 and 39 show typical milling operations being performed on 
die-casting molds. In Fig. 39 the diemaker is shown indicating a pin 
in one corner of the mold cavity, preparatory to doing additional mill- 




Fig. 34. First step in making the Mold— Grinding Surfaces of Blocks 

ing. The block is held in the usual manner by being clamped on the 
bed of the milling machine, and after it has been properly located under 
the cutter head, tools are substituted for the indicator and the milling 




Fig. 35. A Milling Operation on a, Die 

of the cavity is completed. Fig 35 shows one of the sections of the die- 
casting mold which is to be used in producing the casting shown at 
the right of the work. In this case the diemaker is milling the recess 



MACHINES AND METHODS 



43 




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44 



No. 109— DIE CASHING 



plate being held against the under side of the die-plate by means 
of the pinion shaft. The operation being done is the drilling of 
the ejector pin holes. Referring back to Fig. 32, which by the 
way shows the die here illustrated disassembled, the holes being 
drilled are those shown at F for the I'eception of the pins E. The 
method employed is to drill the holes through the die and into tha 




Pigr. 39. Indicatingr a Mold on the MiUlng Machine 

ejector plate, afterward reaming all holes to size and driving the pins 
into position in the ejector plate, while they are allowed to slide freely 
through the die-plate. We will now assume that the ejector box and 
plate have been completed and fitted, a pinion shaft for operating this 
plate also fitted, the lower and upper dies completed by the machining 
operations previously described, and all assembled. The final oper- 
ation of the fitting of the pins is shown in Fig. 41 in which the die- 
maker may be seen filing off the ends of these pins so that when dropped 
to the lower position they will lie flush with the surface. If of uneven 
lengths, these pins will cause irregular spots in the casting. It now 
remains to describe the toggles used for operating the cores which form 
the holes through the three lugs in the casting. One of these toggles, 
of which there are three, is shown at 7. in Fig. 31. and also in Fig. 32. 



MACHINES AND METHODS 



45 



These toggles consist of brackets which are attached to the die-plate, 
and levers which are fulcrumed at the ends of the brackets so that 
their operation works the core pins. It is necessary to remove these 
core pins after each casting has been made and position them before 
another casting can be produced. 

The fitting of the parts of a die-casting mold is one of the most 
important parts of the work. It demands the highest type of work- 




Fig-. 40. DriUing- the Ejector-pin Holes 

manship, for a poorly fitted die means a die which works hard in 
addition to producing poor castings. It is very important that all mov- 
able parts should work freely. Fig. 42 shows the assembling operation 
on a die-casting mold, the casting which is to be duplicated being 
shown in the immediate foreground. These parts must all be screwed 
into their respective places, making the joints as nearly air-tight as 
possible. One cause of poor die-castings arises from the trapping of 
air in the die, and different methods are employed for overcoming this 

trouble. 

Venting the Dies 

There are two methods of preventing air from being trapped in die- 
casting molds; either by constructing the dies so that the air may be 



46 



No. 109— DIE CITING 



exhausted from the mold cavity before admitting the metal, or by 
iVenting the die so that the air may be forced out by the inrushing 
metal. In the first of these methods it is necessary that the joints in 
the mold be made as close as possible, otherwise it will be impossible to 
produce anything like a vacuum in the mold cavity. If, however, it 
has many parts which must be fitted, it is usually considered advisable 
to provide the die with vents consisting of milled recesses a few thous- 
andths inch deep. Several vents are provided, from which the air can 




Fig. 41. Fitting Ejector-pins 

escape when the metal is admitted to the dies. The hot metal, of 
course, "shoots" through them in thin ribbons, but not enough escapes 
to affect the pressure on the metal which goes into the casting. 

No matter how carefully a die may have been constructed, or how 
carefully it has been assembled, there is always a certain amount of 
"babying" to be done before it will work satisfactorily. The casting 
may stick a little here, or there may be a rough spot there, and it is 
the successful elimination of these troubles which constitutes the pro- 
duction of a good die-casting. 



MACHINES AND METHODS 



47 



Die-castingr Metals 
One of the purposes of this book is to correct several erroneous im- 
pressions which are prevalent in regard to die-casting possibilities. 
Many people seem to think that nearly all metals can be die-cast, but as 
a matter of fact, those metals which can be successfully die-cast can be 
numbered on the fingers of one hand, being alloys of lead, zinc, tin, 
copper and antimony. The tin base metals shrink very little, while the 
zinc base metals shrink considerably, and those with a large per 
cent of aluminum have a very high shrinkage. Without doubt, the 
most used die-casting metals are the zinc base metals. A typical metal 
of this class contains about 85 per cent zinc; 8 per cent tin; 4 per cent 
copper and 3 per cent aluminum. The melting point of this metal is 




Fig. 42. AssembUng a Die-casting Mold 

about 850 degrees F. While this alloy is one of the most common, 
it is not by any means the best, as there is too little tin employed, but 
it is a comparatively cheap metal, which probably accounts for its large 
use. This metal is easily affected by heat and cold, and rapidly de- 
teriorates with age. The lead base metals may be typified by 
an alloy containing 80 per cent lead; 15 per cent antimony; 4 per cent 
tin; and 1 per cent copper. This composition melts at approximately 
550 degrees F. and is used for castings subjected to little wear and 
where no great strength is required. The weight of this metal is its 
greatest objection, and it is also quite brittle because of the large per- 
centage of antimony. 

For the best class of die-castings, the tin base metals are employed. 
These range from 60 to 90 per cent tin, and from 2 to 10 per cent 
copper, together with a little antimony. The melting point of a mixture 
of this composition is about 675 degrees F. The castings have a good 
color and they are much better in quality than any of the other alloys. 



JUL 24 }^\i 



48 No. 109— DIE CASfflNG 

It is absolutely eeeential that tin base metals be used for carbureter 
parts or other parts coming in contact with gasoline. Also, the tin 
base metals must be used for parts which come in contact with food 
products, as the lead or zinc alloys have a contaminating effect. 

Aluminum alloys have been cast in France and Germany in limited 
quantities, but very seldom in this country on account of their high 
melting point, as well as their effect upon the die. After aluminum 
alloys have been run in the dies for a short time, the surfaces of the 
molds become pitted. Through some unexplained cause, the metal seems 
to flake out particles of the steel in the molds. When an aluminum 
alloy is to be used, a good mixture is 80 per cent aluminum, 3 per cent 
copper and 17 per cent zinc. This alloy has a high shrinkage and it 
has also the same deteriorating effect upon the dies, but to a much less 
degree than pure aluminum. 



No. 46. Drop Forging. — Lay-out of Plant; Meth- 
ods of Drop Forging; Dies. 

No. 46. Hardening and Tempering. — Hardening 
Plants; Treating Higli-Speed Steel; Hardening 
Gages. 

No. 47. Electric Overhead Cranes. — Design and 
Calculation. 

No. 48. Files and Filing. — Types of Piles; Using 
and Mailing Files. 

No. 49. Girders for Electric Overhead Cranes. 

No. 50. Principles and Practice of Assembling 
Machine Tools, Part I. 

No. 51. Principles and Practice of Assembling 
Machine Tools, Part II. 

No. 52. Advanced Shop Arithmetic for the 
Machinist. 

No. 63. Use of Logarithms and Logarithmic 
Tables. 

No. 54. Solution of Triangles, Part I. — Methods, 
Itules and Examples. 

No. 68. Solution of Triangles, Part II. — Tables 
of Natural Functions. 

No. 56. Ball Bearings, — Principles of Design 
and Construction. 

No. 67. Metal Spinning. — Machines, Tools and 
Methods Used. 

No. 68. Helical and Elliptic Springs. — Calcula- 
tion and Design. 

No. 69. Machines, Tools and Methods of Auto- 
mobile Manufacture. 

No. 60. Construction and Manufacture of Auto- 
mobiles. 

No. 61. Blacksmith Sbop Practice. — Model 
Blacksmith Shop; Welding; Forging of Hooks and 
Chains; Miscellaneous. 

No. 62. Hardness and Durability Testing of 
Metals. 

No. 63. Heat Treatment of Steel. — Hardening, 
Tempering, Case-Hardening. 

No. 64. Gage Making and Lapping. 

No. 65. Formulas and Constants for Gas Engine 
Design. 

No. 66. Heating and Ventilation of Shops and 
Offices. 

No. 67. Boilers. 

No. 68. Boiler Furnaces and Chimneys, 

No. 69. Feed Water Appliances. 

No. 70. Steam Engines. 

No. 71. Steam Turbines. 

No. 72. Pumps, Condensers, Steam and Water 
Piping. 

No. 73. Principles and Applications of Elec- 
tricity.^Statie Electricity; Electrical Measure- 
ments; Batteries. 

No. 74 Principles and Applications of Elec- 
tricity. — Magnetism; Electro-Magnetism; Electro- 
Plating. 

No. 75. Principles and Applications of Elec- 
tricity. — Dynamos; Motors; Electric Railways. 

No. 76. Principles and Applications of Elec- 
tricity. — Electric Lighting. 

No. 77. Principles and Applications of Elec- 
tricity. — Telegraph and Telephone. 

No. 78. Principles and Applications of Elec- 
tricity. — Transmission of Power. 



No. 79. Locomotive Building. — Main and Side 
Rods. 

No. 80. Locomotive Building. — Wheels; Axles; 
Driving Boxes. 

No. 81. Locomotive Building. — Cylinders and 

Frames. 

No. 82. Locomotive Building. — Valve Motion. 

No. 83. Locomotive Building. — Boiler Shop 
Practice. 

No. 84. Locomotive Building. — Erecting. 

No. 85. Mechanical Drawing. — Instruments; 
Materials; Geometrical Problems. 

No. 86. Mechanical Drawing. — Projection. 

No. 87. Mechanical Drawing. — Machine Details. 

No. 88. Mechanical Drawing. — Machine Details. 

No. 89. The Theory of Shrinkage and Forced 
Fits. 

No. 90. Railway Repair Shop Practice. 

No. 91. Operation of Machine Tools. — The 
Lathe, Part I. 

No. 92. Operation of Machine Tools. — The 
Lathe, Part II. 

No. 93. Operation of Machine Tools. — Planer, 
Sbaper, Slotter. 

No. 94. Operation of Machine Tools. — Drilling 

Machines. 

No. 95. Operation of Machine Tools.— Boring 

Machines. 

No. 96. Operation of Machine Tools. — Milling 
Machines, Part I. 

No. 97. Operation of Machine Tools. — Milling 
Machines, Part II. 

No. 98. Operation of Machine Tools. — Grinding 

Machines. 

No. 99. Automatic Screw Machine Practice. — 
Operation of the Brown & Sharpe Automatic Screw 
Machine. 

No. 100. Automatic Screw Machine Practice. — 
Designing and Cutting Cams for the Automatic 
Screw Machine. 

No. 101. Automatic Screw Machine Practice. — 

Circular Forming and Cut-ofif Tools. 

No. 102. Automatic Screw Machine Practice. — 
External Cutting Tools. 

No. 103. Automatic Screw Machine Practice. — 

Internal Cutting Tools. 

No. 104. Automatic Screw Machine Practice. — 
Threading Operations. 

No. 106. Automatic Screw Machine Practice. — 
Knurling Operations. 

No. 106. Automatic Screw Machine Practice. — 
Cross Drilling, Burring and Slotting Operations. 

No. 107. Drop Forging Dies and Die-Sinking. — 

A Complete Treatise on Die-sinking Methods. 

No. 108. Die Casting Machines. 

No. 109. Die Casting. — Methods and Machines 
Used; the Making of Dies for Die Casting. 

No. 110. The Extrusion of Metals. — Machines 
and Methods Used in a Little-known Field of 
Metal Working. 

No. 111. Lathe Bed Design. 

No. 112. Machine Stops, Trips and Locking De- 
vices. — Also includes Reversing Mechanisms and 
Clamping Devices. 



ADDITIONAL TITLES WILL BE ANNOUNCED IN MACHINERY FBOX TIME TO TIME 



LIBRARY OF CONGRESS 



• 003 318 242 9 • 

MACHINERY'S DATA SHEini or^x^xiijo 



Machinery's Data Sheet Books include the well-known series of Data Sheets 
originated by Machinery, and issued monthly as supplements to the publication; 
of these Data Sheets over 500 have been published, and 6,000,000 copies sold. Re- 
vised and greatly amplified, they are now presented in book form, kindred sub- 
jects being grouped together. The pl'ice of each book is 25 cents (one shilling) 
delivered anywhere in the world. 



CONTENTS OF DATA SHEET BOOKS 



No. 1, Screw Threads. — United States, Whit- 
worth, Sharp V- and British Association Threads; 
Briggs Pipe Thread; Oil Well Casing Gages; 
B'ire Hose Connections; Acme, Worm and Metric 
Threads; Maehine, Wood, Lag Screw, and Car- 
riage Bolt Threads, etc. 

No. 2. Screws, Bolts and Nuts. — Fillister-head, 
Headless, Collar-head and Hexagon-head Screws; 
Standard and Special Nuts; T-nuts, T-bolts and 
Washers; Thumb Screws and Nuts; Machine Screw 
Heads; Wood Screws; Tap Drills. 

No. 3. Taps and Dies. — Hand, Maehine. -Tapper 
and Machine Screw Taps: Taper Die Taps; Sellers 
Hobs; Screw Machine Taps; Straight and Taper 
Boiler Taps; Stay-bolt, Washout, and Patch-bolt 
Taps; Pipe Taps and Hobs; Threading Dies. 

No. 4. Reamers, Sockets, Drills and Millinir 
Cutters. — Hand Reamers; Shell Reamers and Ar- 
bors; Pipe Keaniers; Taper Pins and Reamers; 
Brown & Sharpe, Morse and Jarno Taper Sockets 
and Reamers; Drills; Wire Gages; Milling Cutters; 
Setting Angles for Milling Teeth in End Mills and 
Angular Cutters, etc. 

No. 5. Spur Gearing. — Diametral and Circular 
Pitch; Dimensions of Spur Gears; Tal)les of Pitch 
Diameters; Odontograph Tables; Rolling Mill Gear- 
ing; Strength of Spur Gears; Horsepower Trans- 
mitted by Cast-iron and Rawhide Pinions; Design 
of Spur Gears; Epicyclie Gearing. 

No. 6. Bevel, Spiral and Worm Gearing. — Rules 
and Formulas for Bevel Gears; Strength of Bevel 
Gears; Design of Bevel Gears; Rules and Formulas 
for Spiral Gears; Diagram for Cutters for Spiral 
Gears; Rules and Formulas for Worm Gearing, etc. 

No. 7. Shafting, Keys and Keyways.— Horse- 
power of Shafting; Strcngtli of Shafting; Forcing, 
Driving, Shrinking and Running Fits; Woodruff 
Keys; Standard Keys; Gib Keys; Milling Key- 
ways; Duplex Keys. 

No. 8. Bearings, Couplings, Clutches, Crane 
Chain and Hooks. — Pillow Blocks; Babbitted Bear- 
ings; Ball and Roller Bearings; Clamp Couplings; 
Flange Couplings; Tooth Clutches; Crab Couplings; 
Cone Clutches; Universal Joints; Crane Chain; 
Crane Hooks; Drum Scores. 

No. 9. Springs, Slides and Machine Details. — 
Formulas and Tables for Spring Calculations; Ma- 
chine Slides; Machine Handles and Levers; Collars; 
Hand Wheels; Pins" and Cotters; Turn-buckles. 

No. 10. Motor Drive, Speeds and Feeds, Change 
Gearing, and Boring Bars.— Power required for 
Machine Tools: Cutting Speeds and Feeds for 
Carbon and High-speed Steel; Screw Machine 
Speeds and Feeds: Heat Treatment of High-speed 
Steel Tools; Taper Turning; Change Gearing for 
the Lathe; Boring Bars and Tools. 

. Machinery, the leading journal in the 
the 25-cent Reference and Data Books, 
yearly. Foreign subscription, $3.00. 



No. 11. Milling Machine Indexing, Clamping 
Devices and Planer Jacks. — Tables for Milling .Ma- 
chine Indexing; Change Gears for Milling Spirals; 
Angles for setting Indexing Head when Milling 
Clutches; Jig Clamping Devices. 

No. 12. Pipe and Pipe Fittings. — Pipe Threads 
and Gages; Cast-iron Fittings; Bronze Fittings; 
Pipe Flanges; Pipe Bends; Pipe Clamps and 
Hangers. 

No. 13. Boilers and Chimneys. — Flue Spacing 
and Bracing for Boilers: Strength of'Boiler Joints; 
Riveting; Boiler Setting; Chimneys. 

No. 14. Locomotive and Railway Data. — Loco- 
motive Boilers; Bearing Pressures for Locomotive 
Journals; I^ocomotlve Classifications; Rail Sections; 
Frogs, Switches and Cross-overs; Tires; Tractive 
Force; Inertia of Trains; Brake Levers. 

No. 15. Steam and Gas Engines, -.-Saturated 
Steam; Steam Pipe Sizes; Steam Engine Design; 
Volume of Cylinders; Stuffing Boxes; Setting Cor- 
liss Engine Valve Gears; Condenser and Air Pump 
Data; Horsepower of Gasoline Engines; j> jtomo- 
bile Engine Crankshafts, etc. 

No. 16. Mathematical Tables. — Squares of 
Mixed Numbers; Functions of Fractions; Circum- 
ference and Diameters of (Mrdes; Taldes for Spac- 
ing off Circles; Solution of Triangles; Formulas 
for Solving Regular Polygons; Geometrical Pro- 
gression, etc. 

No. 17. Mechanics and Strength of Materials. — 
Work; Energy; Centrifugal Force; Center of Grav- 
ity; Motion; Friction; Pendulum; Falling Bodies; 
Strength of Materials; Strength of Flat I'lates; 
Strength of Thick Cylinders, etc. 

No. 18. Beam Formulas and Strncttiral Design, 
— Beam Formulas; Sectional Moduli of Structural 
Shapes; Beam Charts; Net Areas of Structural 
Angles; Rivet Spacing; Splices for Channels and I- 
beams; Stresses in Roof Trusses, etc. 

No. 19. — Belt, Rope and Chain Drives. — Dimen- 
sions of Pulleys; Weights of Pulleys; Horsepower 
of Belting; Belt Velocity; Angular Belt Drives; 
Horsepower transmitted by Ropes; Sheaves for 
Rope Drive; Bending Stresses in Wire Ropes; 
Sprockets for Link Chains; Formulas and Tables 
for Driving Chain. 

• No. 20. Wiring Diagrams, Heating and Ventila- 
tion, and Miscellaneous Tables. — Typical Motor 
Wiring Diagrams; Resistance of Round Copper 
Wire; Current Densities for Various Contacts and 
Materials; Centrifugal Fan and Blower Capaci- 
ties; Hot Water Main Capacities; Decimal Equiva- 
lents. Metric Conversion Tables. Weights and 
Specific Gravity of Metals, Drafting-room Con. 
ventions, etc. 

machine-building field, the originator of 
Published monthly. Subscription, $2.00 



The Industrial Press, Publishers of Machinery, 
49-55 Lafayette Street, New York City, U. S. A. 



